HF Mobile Installation Tips
With all the different types of installations possible, there are many unique problems that can occur. We have compiled some additional
notes on specified areas.
(1)
GROUNDING ANTENNA: Obtaining a good ground is very important to any HF mobile installation. No matter where your antenna
is mounted, it is highly recommended you run a heavy copper strap or braid (1” to 3”) between body and frame of your vehicle. (NOTE:
Copper wire is not sufficient!) If you have ignition noise problems, it is also recommended to ground the end of your tail pipe to the frame.
1
(2)
OPTIMUM MOUNTING LOCATION: You should always mount your antenna as high on your vehicle and as far away horizontally
from other metal objects as possible. The center of your roof is the best location; however, this is seldom practical or possible for most HF
antenna installations. The next best location is in the center of the driver's side of the trunk lid (mounting on driver side to avoid low
hanging curbside branches or objects). The DIAMOND K400C and K600M series mounts work well with the HV7A.
(3)
TRUNK LID MOUNTING: Probably the best mounting location for most vehicles. Usually, adding one or two copper straps from the
hinge area to car body will improve grounding (and thereby antenna tuning). It is necessary that at least two of the four sockethead screws
on mount penetrate paint to metal for proper grounding. (A little clear nail polish or other acrylic paint may be used to seal around mounting
screws.)
(4)
COAX: If you use an antenna mount other than DIAMOND ANTENNA models K400C or K600M, it is very important to use a
quality 52 ohm coax (RG8U, RG58U, RG213, RG316, Teflon Coax, etc., with at least 95% shield.
(5)
EMI: Electromagnetic Interference is the single greatest concern for HF mobile applications. Route your cable as far from the
vehicles ECM (Engine Control Module) and vehicle's electrical systems as possible. Sometimes a ferrite (clamp) choke may be required on
coax near mount. There are many books on the subject of interference, refer to endnotes for additional information.
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1. J. Seybold, “HF Mobile Installation Tips”, December 1995 QST, pg. 58-60.
2. ARRL, Radio Frequency Interference Tips: How to find it and fix it., The book is available from your favorite amateur radio dealer or
ARRL headquarters.
MX62M Duplexer
LPF 1.6-56; HPF 76-470
Power; 200w CW, 600w PEP
Connectors: Mix-UHF(F);
Ports-UHF(M) w/12” cable
K400C
Trunk/Hatchback Mount
Deluxe UHF type base
Dual-axis adjustable
6½’ RG316 Teflon Coax w/PL-259.
Use Diamond Model C110 for front radio installations.
HV7A Accessory Items
K600M
Trunk Mount
Deluxe trunk mount.
16.5' RG188 and 7mm 5D Coax.
Adjustable Tilt Angle (0-9°)
WARNING! PLEASE READ BEFORE INSTALLATION
BASE STATION ANTENNA
DIAMOND base station antennas are pre-tuned to give best performance on the band(s) for which they are designed, and
no further adjustment should be attempted. Exception: DPGH62 & V2000A require 6m tuning. CP6 & CP6A have tuning instructions included.
BASE ANTENNAS HAVING TYPE-N CONNECTOR
Care should be taken to avoid damage of the center pin of antennas having “TYPE-N” base
connector. Attempted connection of a PL-259 (UHF) or improperly assembled “N” cable connector can damage the antenna connector. Damage to the
antenna connector is not covered by warranty.
MOBILE ANTENNA For ease of installation, DIAMOND ANTENNA MOBILE MOUNTS are strongly recommended.
In some cases, mobile
mounts of different manufacture may not interface well with DIAMOND Antennas. DIAMOND Mobile antennas are pre-tuned to give best possible
performance on the band(s) for which they are designed. In some installations, minor VSWR adjustment may be made by moving the antenna up/down
at the base end. Two set screws at the base allow for adjustment. Do not cut the antenna rods. Use of magnet mounts is not recommended with tall
antennas, i.e. SG2000HD, SG7900, CR627B, & HV7A, etc. Excessive VSWR may occur with the following antennas if used on a magnet mount: CR320A,
NR72BNMO, SG-M911, and SG7000A.
LARGE GVW TRUCK AND OFF ROAD VEHICLES
Due to the excessive vehicle vibration, antennas exceeding 45” are not recommended. In any event,
antennas damaged by excessive vibration are not covered by warranty.
Any tampering, cutting, or attempted adjustment of this antenna beyond our recommendations may void all warranty. If you have any questions, please
call Diamond Customer Service Dept. at (760) 744-0900.
DIAMOND ANTENNA Products are distributed by RF PARTS COMPANY
435 S. Pacific S treet San Marcos, CA 920 78 (770) 614-7443
www.diamondantenna.net
